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Help with an interesting Postgres question: Why isn't an Index Only Scan used on a partition accessed via the parent table?.
CREATE TABLE
INSERT 0 4
| ts | count |
|---|---|
| 2025-02-17 08:00:00 | 0 |
| 2025-02-17 09:00:00 | 1 |
| 2025-02-17 10:00:00 | 1 |
| 2025-02-17 11:00:00 | 1 |
| 2025-02-17 12:00:00 | 1 |
| 2025-02-17 13:00:00 | 1 |
| 2025-02-17 14:00:00 | 1 |
| 2025-02-17 15:00:00 | 1 |
| 2025-02-17 16:00:00 | 1 |
| 2025-02-17 17:00:00 | 1 |
| 2025-02-17 18:00:00 | 2 |
| 2025-02-17 19:00:00 | 2 |
| 2025-02-17 20:00:00 | 2 |
| 2025-02-17 21:00:00 | 0 |
| 2025-02-17 22:00:00 | 0 |
| 2025-02-17 23:00:00 | 0 |
| 2025-02-18 00:00:00 | 0 |
| 2025-02-18 01:00:00 | 0 |
| 2025-02-18 02:00:00 | 0 |
| 2025-02-18 03:00:00 | 0 |
| 2025-02-18 04:00:00 | 0 |
| 2025-02-18 05:00:00 | 0 |
| 2025-02-18 06:00:00 | 0 |
| 2025-02-18 07:00:00 | 0 |
| 2025-02-18 08:00:00 | 0 |
| 2025-02-18 09:00:00 | 0 |
| 2025-02-18 10:00:00 | 0 |
| 2025-02-18 11:00:00 | 0 |
| 2025-02-18 12:00:00 | 0 |
| 2025-02-18 13:00:00 | 0 |
| 2025-02-18 14:00:00 | 0 |
SELECT 31